SLICED KIWI DRYING IN A SOLAR ENERGY AND HEAT PUMP DRYER

A solar energy and heat pump dryer was designed, manufactured and investigated experimentally by drying kiwi. kiwis sliced into 5 mm thickness were dried from initial moisture content 6 g water/g dry matter to final moisture content at 35 °c - 0,53 g water/g dry matter, at 40 °c - 0,25 g water/g dry matter at 45 °c - 0,14 g water/g dry matter and at 50 °c - 0,15 g water/g dry matter. kiwis were dried at the temperature of drying air 50 °c, 45 °c, 40 °c and 35 °c, variable air velocity (0,1-1,0 m/s) and 8,5 hours, 7,5 hours, 7,5 hours and 6,5 hours, respectively. coefficient of performance of heat pump (cophp,h) and whole system coefficient of performance of heat pump (copts) were calculated as average 2,90 and 2,27 for all experiments, respectively. average efficiency of wavy finned air solar collector was calculated as 56,7% for all experiments. the appropriate drying air temperature has been determined as 50 °c for kiwi drying with this experimental study.